Classifying based on Evolution Lesson Goals Explain the difference between evolutionary classification and Linnaean classification Describe how to make and interpret a cladogram. Explain the use of DNA sequences in classification
Explain the difference between evolutionary classification and Linnaean classification Refresher questions: How did the first taxonomists (e.g. Carlos Linnaeus) classify organisms? What is the scientific name for Humans? Explain why organisms scientific names are always in two parts (binomial nomenclature). Do you think the first taxonomists made an errors in their classifications? How does modern Biology correct these errors?
Describe how to make and interpret a cladogram. What is phylogeny? How does a cladogram (or phylogenic tree) represent phylogeny? Task 1 – using your log books - work in pairs to complete a simple cladogram based on the worksheet provided. (make it large and neat – use rulers and pencils if you are a messy artist)
Explain the use of DNA sequences in classification Last year in SC 101 class we used computers to make a cladogram showing the evolutionary relationship between different mammals. Task 2 – (log books continued) Using the same technique (multiple sequence alignment test) we will try and identify an unknown organism by comparing a strand of it’s DNA (for a particular protein) to known organism’s DNA.
Report assignment In log books. Contains a title with a brief introduction (aim, background information about our investigation, key terms explained, evidence of fair test) Hand drawn data table (unknown sample % similarity with each of the known samples) & cladogram showing relatedness. Analysis – using your data propose what the unknown organism is likely to be (claim), support it with your evidence and explain why your evidence supports your claim by explaining the scientific reasoning in this activity.